Although research on leader humility is developing into a prominent literature, the majority of studies have focused on the dyadic or individual rather than collective outcomes of leader humility. Thus, our understanding of the influencing mechanisms and boundary conditions of leader humility remains limited, particularly on the collective work outcome of team creativity, which requires more voluntary effort from employees. Drawing on social cognitive theory and social interdependence theory, our study investigates how leader humility promotes team creativity through team creative efficacy, with the moderation of a contextual factor, task interdependence. We used a sample of 84 teams and 393 employees surveyed in two waves of data collection. Overall, our study yields a mediated moderation model in which the positive indirect effect of leader humility via team creative efficacy on team creativity is stronger when team task interdependence is low rather than high. This study extends our understanding of how leader humility may influence work teams collectively and how the effectiveness of such a leader characteristic may be influenced by a structural factor of the work team. Other theoretical contributions and practical implications are also discussed.